The robustly built Philippine warty pig has a coarse, bristly, blackish coat with a scattering of silvery white hairs on the sides. Long, stiff hairs form a crest running down the middle of the back (2), which is particularly conspicuous in males during the breeding season when if forms a prominent mane over the head crest and neck (2) (3). The medium-length tail has a tuft of long, black hairs at the tip (2) (3), used to swat away flies and signal mood (4). The Philippine warty pig has a long snout, terminating in a flat, mobile disc with the nostrils in the centre (2). The teeth are well-developed, with the large upper and lower canines forming laterally and upwardly protruding tusks in males (3). It has relatively small eyes and ears, and its narrow feet have four toes, but only the two central toes are used for walking (2).

Endemic to the Philippines, where it occurs as two currently recognised subspecies. Sus philippensis philippinesis is found on the northern islands of Luzon, Polillo, Catanduanes and Marinduque, while Sus philippensis mindanensis occurs on the east-central islands of Samar, Biliran, Leyte, Bohol, and the southern islands of Camiguin Sul, Mindanao and Basilan (5) (6) (7).

The Philippine warty pig inhabits grasslands, forest and areas of parang, from sea level to the mountains (2).

Philippine warty pigs may be seen singly, in pairs during the breeding season, or in groups of 7 to 12, consisting of a boar, several sows and young pigs. Although most active at night, they may also move around during the day. They feed on the roots, leaves and tubers of grasses and other plants, using their mobile snouts to plough the ground for such food (2).

Female Philippine warty pigs make nests in which to give birth, situated in carefully selected, concealed areas such as between the buttresses of giant trees surrounded by dense bushes (2). Litters average four to five piglets, but as many as eight may be born in a single litter (3).

Wild pigs are normally shy and retiring but can be dangerous when cornered and will vigorously defend themselves in such a situation. Females in particular can be highly defensive when protecting their young, and will attack potential predators, including people, if threatened (2) (3).

Philippine warty pigs survive in most of the remaining forested areas on the larger islands of the Philippines (8), but intense hunting pressure for its meat and extreme levels of deforestation have resulted in it disappearing from large areas of its historical range, and continue to threaten the remaining populations (1) (2) (8). These threats are being amplified by the rapidly growing human population in the Philippines (1), and illegal clearance of forest for agriculture; the latter also leading to increased incidences of crop damage by wild pigs, which will readily forage on cultivated corn, rice and cassava. Local farmers therefore consider them to be a legitimate target for reprisal hunting (2), and may strongly resist any local protection measures. Finally, hybridisation with free-ranging domestic pigs also threatens the existence of the wild Philippine warty pig (1).

The Philippine warty pig is technically fully protected by Philippine law, though there is little or effective enforcement of the relevant legislation in most areas (3). On the larger islands of the Philippines, such as Luzon and Mindanao, the warty pig occurs in all the principle national parks, although most of these protected areas also exist solely on paper. A number of such parks are known to have been virtually deforested (8), and illegal logging and hunting continues in many other areas (3).

To improve this vulnerable pig’s situation, programmes to educate local people and to alter their negative attitudes towards wild pigs have been recommended. Further research into its exact distribution, status, and biology has also been suggested (8), which will help inform any conservation or management plan for the Philippine warty pig.